Seychelles giant tortoises have been always been thought to be vegetarians... untill now!
Wildlife experts have been left in shock after a giant tortoise attacked and ate a baby bird. The incident was caught on film and is the “first documented observation of a tortoise deliberately attacking and consuming another animal” and represents “an entirely novel behavioral strategy for any tortoise species,” according to a study published on Monday in Current Biology. The video was shot on July 30, 2020, in the forests of Frégate Island in Seychelles, by Anna Zora, who serves as the island’s deputy conservation and sustainability manager. Zora is also the co-author of the paper. "When I saw the tortoise moving in a strange way I sat and watched, and when I realized what it was doing I started filming," said Zora in the statement. Tortoises are found across the world and are almost entirely herbivorous. But this incident changes one's opinion of these "gentle giants". “It’s totally surprising and rather horrifying,” said Justin Gerlach, an island ecologist at Peterhouse, Cambridge in England, according to The New York Times. “The tortoise is deliberately pursuing this bird and kills it, and then eats it. So yeah, it’s hunting.”
Giant tortoise thought to be vegetarian kills and eats bird in slo-mo attack https://t.co/DlGsVk8LtG— The Sun (@TheSun_NI) August 24, 2021
"This is completely unexpected behavior and has never been seen before in wild tortoises," Gerlach, who is the director of studies at Peterhouse, Cambridge and affiliated researcher at the University of Cambridge's Museum of Zoology, said in a statement Monday. "The giant tortoise pursued the tern chick along a log, finally killing the chick and eating it," Gerlach, who led the study, said. "It was a very slow encounter, with the tortoise moving at its normal, slow walking pace -- the whole interaction took seven minutes and was quite horrifying."
What's more interesting to note is that this is probably not the first time the animal may have behaved this way. Gerlach told CNN that the way the tortoise moved towards the chick implied that it was "experienced." "It's moving very deliberately -- it's not just wandering about, it's looking at this tern, and it's walking straight at it, clearly intending to do something. That suggests to me that it's doing it with intent. It knows what it's doing, it's done this before," he said. The herbivorous animals have been spotted on rare occasions "opportunistically" eating carrion, as well as bones and snail shells for calcium. But something like this? Nope! "It's quite common for herbivores to eat a bit of dead animal as a free protein source, essentially. But this is the first video evidence of them deliberately killing in order to eat," he said.
A giant tortoise swallowed a baby bird whole in the Seychelles Islands, revealing an extremely rare example of predation in these animals. https://t.co/DtAGDLxVF5— Motherboard (@motherboard) August 23, 2021
Giant tortoises are said to be the largest herbivores on the Galapagos and Seychelles islands. Researches said that they eat up to 11% of the vegetation. The incident isn't alarming as Gerlach explains that the tortoise's behavior was unlikely to significantly affect tern populations. "It's probably not uncommon for animals to surprise our expectations by eating unexpected things that may just be a one-off," Gerlach explained. "We should try and avoid having too many assumptions about what animals are going to do, or what they are doing. And it really shows the value of observation. Just by watching and recording what animals are doing, you can find really totally unexpected things, things that we couldn't discover deliberately -- it has to be by chance," he said.